FR-A-2 295 894, corresponding to U.S. Pat. No. 4,012,893, calls for transporting several containers simultaneously between destinations that are arranged at angles to one another with the aid of a centrally arranged, controlled-swiveling, and telescoping tappet. In this process the tappet acts as an actual distribution station.
A transfer mechanism that operates in a similar manner between angled stringers of endless belt conveyors is known from DE-U-88 15 126.
EP-A-0 191 158, corresponding to U.S. Pat. No. 4,697,691, indicates a device for the group-wise and row-wise transfer of upright containers that are conveyed in rows. In this case transfer elements are designed as segments of a circle that are eccentrically arranged on a rotating support, whereby said segments rotate or oscillate around the corresponding circle-segment axis. The transfer elements work together with transfer and receiving stations according to the roll-off method, whereby the above-mentioned rolling off causes one container after another to be received by the segments or to be transferred therefrom.
U.S. Pat. No. 5,191,964 also calls for picking up cardboard containers, which pile up in line, in pairs, still in line, and transferring pairs of recesses, also arranged in a straight line, in a rotary transporter or receiving them back from said transporter. The cardboard containers in each pair remain oriented in a line with respect to one another.
U.S. Pat. No. 5,160,558 calls for conveying a stack of plate-type transported objects tangentially in the direction of stacking toward a smooth wheel, directing the stack between the periphery of the wheel and an outer guide that is concentric with said wheel and, while keeping the stack securely attached to the wheel fore and aft with the aid of carriers, moving it along the guide on a circular track until it reaches a removal tappet arrangement that forms an extension of the guide which is curved in the shape of a circular track.
FR-A-1 567 777 also calls for moving a group of bulk items that simultaneously accumulate in a line transversely to the direction of accumulation with the aid of a tappet device.
Procedures for transporting bulk items, such as containers in particular, filled or empty, within the framework of their production or filling with the aid of transport stars are known. In this case the bulk items are transferred from supply conveyors, such as conveyor belts to a transport star, which turns continuously or is clock-controlled to turn at intermittent intervals. During the former star motions, the transfer is frequently accomplished with the aid of screw conveyors.
This invention basically pertains to the transfer technique using star-wheel conveyors, and it matters little whether said conveyors operate at intermittent intervals or continuously.
During the transfer from the front-end conveyor to the conveyor star or vice versa, as EP-A-0 191 158 indicates in an improved version, it is common practice to load and unload one transport recess in the star after the other.
In this process, as mentioned above, such transport techniques are used in the manufacturing, testing, and checking of bulk items as well as being used on containers to fill said items. In the case of complete systems used for this purpose, the throughput rate is determined by the slowest element in the processing and transport sequence.
With this in mind, this invention has set itself the goal of creating a procedure and a transport arrangement of the type mentioned above by means of which the transport rate that can be achieved per unit of time is increased. This is accomplished by the procedure of the invention and the arrangement of the invention wherein before the bulk items are directed into transport recessed, the mutual positions of at least two bulk items are established in accordance with the curvature of the mutual positions of successive conveyor recesses on the star, and wherein the bulk items, with intervals between bulk items that correspond to the intervals of successive transport recesses on the star, are simultaneously transferred to at least two conveyor recesses on the star.
Because the mutual positioning of the bulk items is determined in accordance with the curvature of the mutual positions of two and preferably three or more transport recesses that follow one right after the other on the star and the bulk items are simultaneously transferred in this mutual arrangement to the corresponding number of transport recesses in the star, this produces a substantial increase in the bulk-item throughput rate which is determined by the loading procedure alone.
In this process it is basically irrelevant whether transport takes place at intermittent intervals, i.e., in cycles, or continuously. Even in the latter case the procedure of the invention can be used if at least two bulk items are fed into the transport recesses of the transport star at the right instant.
In addition, in transports of the type under discussion here, the bulk items are conveyed, temporarily resting against one another, toward the conveyor star. Usually, however, transport stars have an angular gap between transport recesses. Taking this into account, it is proposed that, before reaching the transport recesses, the gaps between bulk items be adjusted to match the gaps between the transport recesses. It is preferable for both alternatives to be offered.
Although the establishment of the curved mutual positions of the bulk items on their transport track can be done long before reaching the transfer area by, for example, gradually converting a straight conveyor belt into a correspondingly curved one, in accordance with the invention it is proposed that this transition be made only when the bulk items begin to be pushed into the transfer area, preferably by pushing them into a curved guide. With respect to the alternative mentioned above, this leads to considerably lower production costs.
A transport arrangement according to the invention for accomplishing the task mentioned in the beginning of this description comprises an intermediate conveyor having carriers, each designed for a bulk-item group comprising at least two bulk items and having transport surfaces that are curved in accordance with the mutual positions of successive transport recesses on the star.
The procedure of the invention and the transport arrangement of the invention are particularly suitable for inspection systems for bulk items, while they are particularly suitable for rotationally symmetrical containers, especially for filled or empty jars or vials as noted above. Vials are defined as glass-jar-like containers with rubber plugs and metal sealing strips, such as those used for pharmaceuticals and medications, e.g., vaccines.
The invention is explained below by referring to two figures.